As of the latest Form 4 filed May 7, 2026.
What Amentum Holdings Inc. insiders — officers, directors and 10% owners — have bought and sold in their own stock, straight from their SEC Form 4 filings. Values are shares × the reported transaction price where both are disclosed.
Newest filing first — the 28 most recent filings for AMTM.
| Filed | Trade date | Insider | Transaction | Shares | Price | Value | 10b5-1 | Filing |
|---|---|---|---|---|---|---|---|---|
| 2026-05-07 | 2026-05-06 | Heller John E. Chief Executive Officer | FTax | −8.18K | $24.89 | $204K | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Heller John E., Chief Executive Officer | MExercise | +18.1K | — | — | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Mullen Sean Thomas Chief Growth Officer | FTax | −2.76K | $24.89 | $68.7K | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Mullen Sean Thomas, Chief Growth Officer | MExercise | +9.07K | — | — | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Johnson Travis Barton Chief Financial Officer | FTax | −4.10K | $24.89 | $102K | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Johnson Travis Barton, Chief Financial Officer | MExercise | +13.6K | — | — | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Bruning Jill L Chief Technology Officer | FTax | −2.73K | $24.89 | $68.0K | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Bruning Jill L, Chief Technology Officer | MExercise | +9.07K | — | — | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Arnette Stephen A Chief Operating Officer | FTax | −3.31K | $24.89 | $82.5K | No | Form 4 ↗ |
| 2026-05-07 | 2026-05-06 | Arnette Stephen A, Chief Operating Officer | MExercise | +13.6K | — | — | No | Form 4 ↗ |
| 2026-03-05 | 2026-03-04 | Bruning Jill L Chief Technology Officer | GGift | −30.0K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-03-04 | 2026-03-02 | Arnette Stephen A Chief Operating Officer | FTax | −750.00 | $30.70 | $23.0K | No | Form 4 ↗ |
| 2026-03-04 | 2026-03-02 | Arnette Stephen A, Chief Operating Officer | MExercise | +2.81K | — | — | No | Form 4 ↗ |
| 2026-02-18 | 2026-02-17 | St. Mary Michele T Chief Legal Officer & GC | FTax | −2.31K | $30.05 | $69.4K | No | Form 4 ↗ |
| 2026-02-18 | 2026-02-17 | St. Mary Michele T, Chief Legal Officer & GC | MExercise | +7.08K | — | — | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | IRELAND SUSAN LESLIE Director | AAward | +5.06K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Rowland Sandra E. Director | AAward | +5.06K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Rowland Sandra E., Director | MExercise | +11.6K | — | — | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Brooks Vincent K Director | AAward | +5.06K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Brooks Vincent K, Director | MExercise | +11.6K | — | — | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | EBERHART RALPH E Director | AAward | +5.06K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | EBERHART RALPH E, Director | MExercise | +11.6K | — | — | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Loughran Barbara Director | AAward | +5.06K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Thompson Christopher M.T. Director | AAward | +5.06K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Vollmer John C. Director | AAward | +5.06K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Vollmer John C., Director | MExercise | +11.6K | — | — | No | Form 4 ↗ |
| 2026-01-29 | 2026-01-28 | Heller John E. Chief Executive Officer | FTax | −19.8K | $35.71 | $706K | No | Form 4 ↗ |
| 2026-01-29 | 2026-01-28 | Heller John E., Chief Executive Officer | MExercise | +52.0K | — | — | No | Form 4 ↗ |
Insiders — a company’s officers, directors and holders of more than 10% of its stock — must report any trade in that stock to the SEC on a Form 4 within two business days. Each row here is one transaction from those filings.
The transaction code tells you what happened: Purchase (P) and Sale (S) are open-market trades — the ones markets watch most; Award (A) is a granted stock or unit, Option exercise (M) converts options into shares, and Gift (G) is a transfer for no consideration. Awards, exercises and gifts are largely compensation or administrative, not a directional bet.
One caveat on sales: many are made under a Rule 10b5-1 plan scheduled months in advance, so a sale is not automatically a bearish signal. Insider activity is a noisy input — read it alongside the filings, not on its own.
See also AMTM’s full analysis or the market-wide insider trading feed. The tabs above jump to AMTM’s other SEC data.
Source: SEC Form 4 filings for AMTM, parsed from EDGAR. Transaction prices are as reported in the filing — SEC public-domain data, not market quotes. Values are shares × reported price where both are disclosed; grants and gifts often carry no price. A delayed record of what insiders reported, not a live position or a recommendation.
Research and education only — not financial advice. TENKis not a registered investment adviser or broker-dealer and gives no personalized advice. Every call is impersonal — identical for all users, generated on a schedule from SEC filings plus a delayed/third-party price feed — may be wrong or out of date, and is not a recommendation to buy or sell any security. The operator and an affiliated trading operation may hold or trade the securities TENK rates; see Disclosures. Past performance does not guarantee future results. Do your own research.